Hesitation
 

ok ill start by saying thing problem started after took it to the mub pit on our last trip bout 6 months ago. ive been going through things to try figure it out. it only happens when I accerlerate hard, if I ease on the gas pedal itdoesnt do it. ive replaced my fuel pump and filter and cleaned out the gas tank thinking there was trash. I got a can of mass air flow sensor cleaner and used that it didn't help. me personly I think its a air issue somewhere as there are some air lines under the hood that aint being used. when we first got it the 4x4 didn't work there was a line that wasn't hook up right I think I swithed the lines and it started working however there is one that was hooked up to the smog pump thing that is now not hooked up thinking I should get a spliter and try hooking it back together so that they both are hooked up.any suggestions will be helpful. thanks in advance for any responces to this issue.

In the off chance you haven't already done so, I suggest checking that the vacuum lines don't have any leaks and also that the entrance to air filter box is not constricted (since you mentioned the mud).